Because trainers inject code into running processes, most antivirus software (Windows Defender, Norton) will flag them as "HackTool:Win64/GameHack." This is a false positive, but you must add an exclusion folder.
For the uninitiated, "Fling" is a well-known username in the modding scene. They are famous for creating offline "trainers"—small programs that modify a game’s memory to give the player unlimited health, ammo, or god mode.
: Prevents the player from taking damage or dying.